Fix building error of missing end-group for Android. (#8680)

Author: Xreki

CMakeLists.txt

@@ -166,11 +166,11 @@ include_directories("${CMAKE_CURRENT_BINARY_DIR}/proto")
 include_directories("${CMAKE_CURRENT_BINARY_DIR}/go/pserver/client/c")
 
 set(EXTERNAL_LIBS
-    ${GFLAGS_LIBRARIES}
-    ${GLOG_LIBRARIES}
-    ${CBLAS_LIBRARIES}
-    ${PROTOBUF_LIBRARY}
-    ${ZLIB_LIBRARIES}
+    gflags
+    glog
+    cblas
+    protobuf
+    zlib
     ${PYTHON_LIBRARIES}
 )
 

cmake/external/zlib.cmake

@@ -28,7 +28,7 @@ ENDIF(WIN32)
 INCLUDE_DIRECTORIES(${ZLIB_INCLUDE_DIR})
 
 ExternalProject_Add(
-    zlib
+    extern_zlib
     ${EXTERNAL_PROJECT_LOG_ARGS}
     GIT_REPOSITORY  "https://github.com/madler/zlib.git"
     GIT_TAG         "v1.2.8"
@@ -49,9 +49,11 @@ ExternalProject_Add(
                      -DCMAKE_BUILD_TYPE:STRING=${THIRD_PARTY_BUILD_TYPE}
 )
 
+ADD_LIBRARY(zlib STATIC IMPORTED GLOBAL)
+SET_PROPERTY(TARGET zlib PROPERTY IMPORTED_LOCATION ${ZLIB_LIBRARIES})
+ADD_DEPENDENCIES(zlib extern_zlib)
+
 LIST(APPEND external_project_dependencies zlib)
-ADD_LIBRARY(zlib_target STATIC IMPORTED GLOBAL)
-SET_PROPERTY(TARGET zlib_target PROPERTY IMPORTED_LOCATION ${ZLIB_LIBRARIES})
 
 IF(WITH_C_API)
   INSTALL(DIRECTORY ${ZLIB_INCLUDE_DIR} DESTINATION third_party/zlib)

cmake/generic.cmake

@@ -104,7 +104,9 @@ function(merge_static_libs TARGET_NAME)
   foreach(lib ${libs})
     list(APPEND libs_deps ${${lib}_LIB_DEPENDS})
   endforeach()
-  list(REMOVE_DUPLICATES libs_deps)
+  if(libs_deps)
+    list(REMOVE_DUPLICATES libs_deps)
+  endif()
 
   # To produce a library we need at least one source file.
   # It is created by add_custom_command below and will helps
@@ -191,10 +193,13 @@ function(cc_library TARGET_NAME)
         list(REMOVE_ITEM cc_library_DEPS warpctc)
         add_dependencies(${TARGET_NAME} warpctc)
       endif()
-      # Support linking flags: --whole-archive (Linux) / -force_load (MacOS)
-      target_circle_link_libraries(${TARGET_NAME} ${cc_library_DEPS})
       if("${cc_library_DEPS}" MATCHES "ARCHIVE_START")
+        # Support linking flags: --whole-archive (Linux) / -force_load (MacOS).
+        # WARNING: Please don't use ARCHIVE_START&ARCHIVE_END if TARGET_NAME will be linked by other libraries.
+        target_circle_link_libraries(${TARGET_NAME} ${cc_library_DEPS})
         list(REMOVE_ITEM cc_library_DEPS ARCHIVE_START ARCHIVE_END)
+      else()
+        target_link_libraries(${TARGET_NAME} ${cc_library_DEPS})
       endif()
       add_dependencies(${TARGET_NAME} ${cc_library_DEPS})
     endif()